Huh. I am not ruling out that there may be something to it, but this article somehow triggers my bullshit detector. A lot of very flowery language, with what looks to me like wild speculation. And some of the claims about electricity are just... weird.

G Chevalier and JL Oschman are independent contractors for EarthFx Inc., the company sponsoring earthing research, and own a small percentage of shares in the company. Richard Brown is an independent contractor for EarthFx Inc., the company sponsoring earthing research.

Ah yes, here we go. Doesn't inspire confidence in them being unbiased.

Wearing rubber slippers, measured against (presumably) good ground. Granted, my voltmeter is absolute trash, but I can do it with a decent benchtop one at work and I'm confident the value will be similar.

I'd be much more concerned about EMI / "electro-smog", all the electromagnetic fields and radio emissions around us. Those are very much measurable, they don't really care about any arbitrary concept like "ground potential" whatever that might be, and your body works like a (bad) antenna, if you want it or not.

I am still not particularly concerned about them, fuck, I work in microwave tech and am a ham radio guy, if it has any negative effects, I'm certain I'll notice them first. I also occasionally drink, sometimes eat meat, exist in a car-rich environment, am full of microplastic and exercise way too litte, so it is still very far down the list of my health concerns.